Odometer for a mobile apparatus, and method

Abstract

An odometer system for a vehicle or mobile apparatus 1 are described. The odometer comprises a distance-determining device 2 configured to transmit a beam of radiation, such as a laser beam 13 and to determine, from reflected radiation of the beam 13 off a target surface 11 remote from the distance-determining device, a measurement value of the instantaneous separation distance Dm between a mobile measurement reference point 6, 11 of the vehicle 1 and a stationary measurement reference point 3 remote from the vehicle 1. The distance-determining device 2 is configured to be located at the stationary measurement reference point 3 and to direct the radiation beam 13 towards the remote target surface 11 located at the mobile measurement reference point 6, 11, and the odometer device 2 comprises communication means 7 for wirelessly communicating the measurement value to a data receiving means 7′ at the vehicle 1.

1 . An odometer system for a mobile apparatus, the system comprising:
 a first distance determining device configured to transmit a beam of radiation from a stationary measurement reference point remote from the mobile apparatus to a target surface at the mobile apparatus and to determine, from reflected radiation of the beam off the target surface, a measurement value of an instantaneous separation distance between the target surface and the stationary measurement reference point, data receiving means at the mobile apparatus;   communication means for wirelessly communicating the measurement value to a data receiving means at the mobile apparatus, wherein the data receiving means comprises offsetting or zeroing means for identifying a reference start point for measuring a travelled distance of the mobile apparatus along a path, and for determining the travelled distance, using subsequently received measurement values, with respect to the identified start point.   
     
     
         2 . The odometer system of  claim 1 , comprising target tracking means for training the beam on the remote target surface as the mobile apparatus moves. 
     
     
         3 . The odometer system of  claim 2 , wherein the target tracking means comprises target offset determining means for determining an offset angle between an angular position of the remote target surface relative to the stationary measurement reference point and the transmission direction of the beam, and beam orientation adjustment means for automatically adjusting the transmission direction of the beam in dependence on the offset angle. 
     
     
         4 . The odometer system of  claim 3 , wherein the target offset determining means comprises:
 beam position determining means for determining a position of the beam,   optical image acquisition means for acquiring an image of the remote target surface,   first pattern recognition means for detecting, in the image, a predetermined pattern of the remote target surface, and   pattern position determining means for determining a position of the pattern,   wherein the target offset determining means is configured for determining an offset distance between the positions of the beam and the pattern.   
     
     
         5 . The odometer system of  claim 4 , wherein the beam position determining means comprises second pattern recognition means for detecting, in the image, the reflection of the beam. 
     
     
         6 . The odometer system of  claim 3 , wherein the first distance determining device comprises angular displacement drive means for rotational displacement of the beam relative to a stationary mount, whereby the beam position determining means is configured to determine an angular orientation of the beam from information from the transmission beam drive means. 
     
     
         7 . The odometer system of  claim 1 , wherein the instantaneous measurement value comprises an incremental change in the separation distance since a previous distance measurement. 
     
     
         8 . The odometer system of  claim 4 , wherein the optical image acquisition means, the first pattern recognition means and/or the second pattern recognition means comprise an optical or digital zoom means for varying the scale of the image, the pattern or the reflection in dependence on the separation distance. 
     
     
         9 . The odometer system of  claim 6 , wherein the drive means comprises means for varying a displacement resolution of the drive means in dependence on the separation distance. 
     
     
         10 . The odometer system of  claim 1 , comprising means for detecting an out-of-range condition of the beam alignment with the target surface, wherein the communication means is configured to stop communicating the measured value in the event of said out-of-range condition. 
     
     
         11 . The odometer system of  claim 1 , wherein the mobile apparatus is a marking apparatus for applying a marking substance to a ground surface. 
     
     
         12 . The odometer system of  claim 1 , wherein the path is a straight path. 
     
     
         13 . The odometer system of  claim 1 , wherein the path is a curved path. 
     
     
         14 . The odometer system of  claim 1 , comprising means for indicating the current distance travelled by the mobile apparatus to an operator of the mobile apparatus. 
     
     
         15 . The odometer system of  claim 1 , comprising a control means for controlling a speed of the mobile apparatus, or an operational parameter of an equipment of the mobile apparatus, in dependence on the travelled distance. 
     
     
         16 . The odometer system of  claim 1 , further comprising second and/or third distance determining devices, radiation beams of the first, second and/or third distance determining devices being oriented to different target surfaces or different regions of the same target surface, wherein the odometer system comprises target orientation determining means for, using first, second and/or third measurement values from the first, second and/or third distance determining devices, determining a spatial orientation of the target surface, the target surfaces and/or the mobile apparatus. 
     
     
         17 . A method of measuring a distance travelled by a mobile apparatus, characterised by using an odometer system according to  claim 1 . 
     
     
         18 . A method of measuring a distance travelled by a mobile apparatus, characterised by using an odometer system according to  claim 16 .